Radiator cap with release valve



Dec. 3, 1963 T. B. MILLER ETAL RADIATOR CAP WITH RELEASE VALVE 2 Sheets-Sheet 1 Filed April 18, 1961 mmvroa. Z4 6 f/Wderc? W W/2522x220 TORNEY Dec. 3, 1963 MILLER ETAL 3,112,840

RADIATOR CAP WITH RELEASE VALVE Filed April 18, 1961 2 Sheets-Sheet 2 INVENTOR.

United States Patent 3,112,84tl RADIATQR CAP wrru RELEASE VALVE Tom l3. Miller, Grand Blanc, and Harry W. Nirnmo,

Davlson, Mich assignors to General Motors Corporation, Detroit, Mich, a corporation oit Delaware Filed Apr. 18, 1961, See. No. 1%,752 1 Claim. (@l. 220-44) This invention relates to closures or caps such as employed on automobile radiators.

The primary function of such a cap is to seal a radiator neck and thereby close an engine cooling system and such a system is customarily pressurized for increased cooling efficiency. Pressures have increased in such systems in recent years but it the pressure in a given cooling system increases beyond a predetermined value it is conventional to have the excess pressure automatically reieved through a vent by means of a relief valve built into the cap. Also, if the cooling system pressure falls too low, a vacuum operated valve in the cap admits air preventing collapse of any part of the system. A valve with such features is disclosed in the United States Patent 2,266,314, issued December 16, 1941, in the name of l. E. Eshbaugh.

in the event a given cooling system is pressurized, re moval or opening of the cap causes a sudden release in pressure and a consequent sudden increase in boiling of the engine coolant. The result often occurs that a rush of boiling coolant issues from the filler neck with an accompanying danger to the person removing the cap.

An object of the present invention is to provide an improved radiator cap with a manually operated and safe pressure release in an arrangement having no protruding lever or plunger detracting from its structural compactness.

A feature of the present invention is a radiator cap with a rotary cam arrangement operative about the axis or" the cap to ellect safe venting of a system to which the cap may be applied.

This and other features of the invention will become apparent from the following description.

In the drawings:

FIGURE 1 is a sectional view of one form of a radiator cap in which the present invention is embodied and a conventional radiator neck to which the cap is applied, the cap being shown with its parts positioned to close the radiator;

FIGURE 2 is a view similar to that of FIGURE 1 but with the parts positioned for venting the radiator;

FIGURE 3 is a top or plan View of the cap shown in FIGURE 1; and

FIGURE 4 is an exploded and perspective view of cam arrangement parts utilized in the cap of FIGURES l, 2 and 3.

In FIGURES l and 2 of the drawings a portion it is depicted as a header tank part of a conventional automobile radiator. The coolant level when the radiator is full is shown at 12. A conventional filler neck 14 is soldered as at 15 to the radiator portion it and bears a lower inner valve seat it) defining an opening 2th into the radiator. The upper end of the neck 14 bears a conventional outurned flange 22 having diagonally opposed notches and cam surfaces for engaging inturned tangs 2d and 2-5 of cover means generally indicated at 28. The neck 14 has a conventional vent 25 located betwee the seat l8 and the flange 22. The cover means 28 includes a metallic cup 3% having a peripheral downturned flange 32 from which the tangs 24 and 26 are formed. The cup 3% is circular except for two oppositely disposed ears 3-, and 36 (FIGURE 3) fac itating manual tightening or removal of the cap with respect to the neck. An intermediate portion 33 of the cup ddllfl ld Patented Dec. 3, 1963 ice 30 is depressed nonrotatably to receive the tabs at; and 42 of a cam member 44. The latter is apertured at 46 freely to receive a shaft 48. The margin of the cam member 44 is thickened or formed at diametrically opposed areas to form two upwardly directed cam surfaces 49 and St The inner margin of the cam member 44 is so formed on the underside as to receive a sealing washer 52 which forms a seal with the shaft and is firmly held in position between the cover member 30 and the cam member 44. A spring sealing disk 54 is held on the underside of the metallic cup 30 by means of an outturned flange 56 formed on the cup 30 and also by coiled springs as will further appear.

A plastic handle as overlies the metallic cup 30 and bears two arcuate cam surfaces 62 and 64 formed with radii such that these surfaces are adapted to engage the cam surfaces 49 and Eli when the handle is rotated about the shaft 48. Legends may be placed on the plastic handle 60 and the cup 3t) as indicated in FIGURE 3. The upper end of the shaft 43 is formed pivotally to retain the handle oil on the cap. The lower end of the shaft 48 is provided with two shoulders as and 6d. The shoulder 66 is utilized to retain a coil spring "ill in compression against the underside of the valve spring disk 54 thereby preventing rattling of the parts when positioned as shown in FIGURE 1--tl1at is, when the shoulder 68 is in the clear. A deepened and lengthened portion '71 of the plastic handle facilitates operation.

Valve means is generally indicated at 72 as being retained on the underside of the cover means 22; and is held to the handle 6t and metallic cup 3% by means of the shoulder 6?; on the shaft 43. The latter passes through an aperture '75 formed in an inverted cup 76 forming a part of the valve means. The shoulder 68 on the shaft 48 is adapted to be maintained in engagement with the inverted cup '76 by means of a coil spring is; acting between the spring disk 54 and a shoulder 80 formed on the cup when the cap is removed from the neck 14. The valve means 72 also includes a vacuum relief valve arrangement 32 which constitutes two inverted cups 84 and 8d. The cup 84 is fitted tightly within the cup 76 and the cup 86 is loosely held to and within the cup 8 by means of a spring loaded pin $6. An aperture 92 is formed in the cup 84 to permit admission or air to the radiator it? when a vacuum in the latter exceeds a predetermined value as established by the loading of a spring 94- as will be understood. A sealing disk 96 is utilized between the two cups 8-, and S6 to form a seal under ordinary operating pressure conditions. A fiange ltlil on the cup 84 serves to retain a main sealing washer 1&2 in position on an outturned flange 19d of the cup '76. The washer N2 is adapted to engage the seat 18 of the filler neck.

The operation of the radiator cap may be understood from the above but it may be stated that in operation the valve parts are positioned as shown in FIGURE 1, a seal being formed at seat 18 by the washer ill-2; effectively closing the radiator ill at pressures the maximum of which is determined by the loading of the spring '73. If too lowa pressure should occur in the radiator, the cup 82; will lower against the spring 92 and admit by way of the vent line and the opening 92. If the pressure in. the radiator It should exceed a predetermined maximum value, it will compress the spring 78 and vent the radiator by disengagement of the washer 1&2 with its seat 13.

in the event an operator desires to remove the cap from the radiator, he will first turn the plastic handle at to the open position causing the cam surfaces 49 and 5d at 62 and a l to be efiective in moving the valve means 72 tom the seat 1 .3 as shown in FIGURE 2. The cam means will first assume the loading of the spring ill and then, through the shoulder 68, the loading of the spring 73, The radiator will then be eflectively vented by way of the vent 25 and sudden release of pressure will cause an outflow in such a Way that it may be directed to the ground and away from the operator. When the boiling stops the cover means 28 together with the plastic handle (it) may be rotated together and with respect to the filier neck and be removed with complete safety. Prior to or when the cap is replaced on the filler neck, the handle 66 must obviously be returned to sealed position so that when the metallic cup 28 is turned and firmly locked on the neck, the sealing Washer will engage the seat 13 under the loading of the spring 78 as shown in FIGURE 1.

We claim:

A radiator cap comprising cover means for a radiator neck opening, valve means of smaller diameter than said cap adapted to fit within said radiator neck opening, a shaft having one end supporting said valve means and having its other end extending through said cover means, means providing diametrically opposed upwardly directed CJI earn surfaces on said cover means, each of said surfaces 20 converging substantially to an apex, a rotatable handle member overlying said cover means and being secured to said other end of said shaft, means providing downwardly extending opposed arcuate cams on said handie member, said cams having substantially planar surfaces adapted to engage said cam surfaces on said cover means, said planar surfaces contacting said apexes to hold said valve means in an open position and said apexes being receivable between said cams when said valve means is moved to its closed position, first spring means interposed between said cover means and said valve means and urging said valve means away from said cover means, and second spring means interposed between said cover means and said one end of said shaft thereby said cam surfaces on said handle member are maintained in engagement with said cam surfaces on said cover means.

References Cited in the file of this patent UNITED STATES PATENTS 1,652,696 Beard et al Dec. 13, 1927 2,009,696 King July 30, 1935 2,964,214 Stannard Dec. 13, 1960 2,990,971 Enell July 4, 1961 

